mirror of
https://github.com/Kiritow/OJ-Problems-Source.git
synced 2024-03-22 13:11:29 +08:00
140 lines
2.7 KiB
C++
140 lines
2.7 KiB
C++
#include <cstdio>
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#include <iostream>
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#include <algorithm>
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#include <ctime>
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#include <cctype>
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#include <cmath>
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#include <string>
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#include <cstring>
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#include <stack>
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#include <queue>
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#include <list>
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#include <vector>
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#include <map>
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#include <set>
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#define sqr(x) ((x)*(x))
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#define LL long long
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#define INF 0x3f3f3f3f
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#define PI acos(-1.0)
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#define eps 1e-10
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#define mod 1000000007
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using namespace std;
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int cnt=0;
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typedef pair <LL,LL> qf;
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qf operator + (qf a,qf b)
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{
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return make_pair((a.first+b.first)%mod,(a.second+b.second)%mod);
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}
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qf operator * (qf a,qf b)
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{
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if (a.first<0) a.first+=mod;
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if (b.first<0) b.first+=mod;
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if (a.second<0) a.second+=mod;
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if (b.second<0) b.second+=mod;
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return make_pair((((LL)a.first*(LL)b.first)%mod+((LL)a.second*(LL)b.second)%mod*5ll)%mod,
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(((LL)a.first*(LL)b.second)%mod+((LL)a.second*(LL)b.first)%mod)%mod);
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}
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qf pow(qf a, LL x)
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{
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qf res(1,0);
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qf multi=a;
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while (x)
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{
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if (x&1)
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{
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res=res*multi;
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}
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multi=multi*multi;
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x/=2;
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}
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return res;
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}
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LL pow(LL a,LL b)
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{
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LL res=1;
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LL multi=a;
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while (b)
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{
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if (b&1)
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{
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res=res*multi%mod;
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}
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multi=multi*multi%mod;
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b/=2;
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}
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return res;
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}
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qf acce(qf a,LL b)
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{
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qf ans=make_pair(1,0);
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qf powe=a;
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qf sum=a;
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qf multi=make_pair(1,0);
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while (b)
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{
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if (b&1)
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{
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ans=ans+(multi*sum);
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multi=multi*powe;
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}
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sum=sum*(powe+make_pair(1,0));
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powe=powe*powe;
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b/=2;
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}
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return ans;
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}
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LL inv[100005];
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qf r1[100005],r2[100005];
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void egcd (LL a,LL b,LL &x,LL &y)
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{
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if (b==0)
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{
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x=1,y=0;
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return ;
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}
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egcd(b,a%b,x,y);
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LL t=x;
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x=y;y=t-a/b*y;
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}
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int main()
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{
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LL x,y;
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for (LL i=1;i<=100000;i++)
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{
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egcd(i,mod,x,y);
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x=(x+mod)%mod;
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inv[i]=x;
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}
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r1[0]=make_pair(1,0);
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r2[0]=make_pair(1,0);
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for (int i=1;i<=100000;i++)
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{
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r1[i]=r1[i-1]*make_pair(1,1);
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r2[i]=r2[i-1]*make_pair(1,-1);
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}
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int T;
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scanf("%d",&T);
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while (T--)
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{
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cnt=0;
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LL n,m;
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scanf("%I64d%I64d",&n,&m);
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qf ans=make_pair(0,0);
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LL Ca=1;
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LL v=pow(inv[2],m);
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for (LL i=0;i<=m;i++)
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{
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qf p(Ca,0);
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qf tmp=r1[i]*r2[m-i]*make_pair(v,0);
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tmp=acce(tmp,n);
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tmp=tmp*p;
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ans=ans+tmp;
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Ca=Ca*(m-i)%mod;
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Ca=Ca*inv[i+1]%mod;
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}
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LL aa=(LL)ans.first;
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printf("%I64d\n",aa);
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}
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return 0;
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}
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